- Redesigned the message view screen; tap the message header containing sender/recipient names to see more details
- Added a setting for three different message list densities: compact, default, relaxed
- Added better support for right-to-left languages when composing messages
- Search now also considers recipient addresses
- Fixed a bug where notifications would sometimes reappear shortly after having been dismissed
- IMAP: Fixed a bug where sometimes authentication errors were silently ignored
- Various other small bug fixes and improvements; see changes for versions 6.5xx
